(Ця стаття також доступна українською мовою тут.)

Under international law, Russia’s invasion of Ukraine without any doubt constitutes an act of “aggression” which manifestly violates the United Nations Charter. As such, it gives rise to individual criminal responsibility of those who were “in a position effectively to exercise control over or to direct the political or military action of a[n aggressive] State” (Art.8bis of the Rome Statute of the International Criminal Court (ICC)). Due to his overwhelming control over the state apparatus, President Vladimir Putin is an obvious candidate who satisfies this so-called leadership clause (“control or direct”), which I previously argued to be part of customary international law. The question that looms is who else apart from the top-state leadership may be responsible for aggressive war in Ukraine.

Could criminal liability extend, for example, to senior executives of the Wagner Group and other “private” actors involved in Russia’s aggression against Ukraine?

During the drafting process of the Rome Statute’s definition of the crime of aggression, Kevin Jon Heller powerfully argued that the current leadership requirement is too narrow to capture anyone besides the immediate political and military leadership of a state. On this view, the new definition retreats from the Nuremberg legacy as it effectively excludes private individuals (such as economic actors) who were seen as responsible during the trials following World War II. In her recent post, Carrie McDougall reaffirms her strong position on this narrow interpretation. Unlike Heller, she looks sympathetically toward this outcome. For her the crime of aggression is “about punishing those responsible for deciding to use inter-State armed force aggressively” and deterring such acts (p. 232).

Against that background, this article will argue that private individuals are able to exercise control over the state policy and consequently may be prosecuted for complicity in the crime of aggression.

What is the normative content of the leadership clause?

It is now widely accepted that atrocity crimes are phenomena generally marked with an organizational structure. Behind the actual perpetration there is typically a state or state-like organization which creates the normative climate allowing the commission of atrocities. Direct perpetration is thus carried out by rank-and-file soldiers following superiors’ orders, which emanate from structural policies generated by the organizational leadership. This constellation makes the prosecutor’s life dreadfully difficult when ascribing responsibility to those at the apex of criminal organizations who are usually “far behind the scenes” with “no blood on their hands.”

Direct perpetration of the crime of aggression is likewise carried out by common foot soldiers who are, in this case, excluded from criminal liability since they do not meet the leadership requirement. This peculiarity of the crime of aggression shifts the focus directly to the leaders responsible for formulating and executing aggressive state policies. To that end, since followers are categorically excluded from criminal liability, it may be easier to connect leaders with the underlying criminal act. This important feature of prosecuting aggression was explicitly acknowledged in a recent statement made by a group of prominent lawyers and public figures: “The ICC will be able to hold individuals responsible for the crimes that it deals with where there is specific evidence linking them to particular acts and policies. However, it may in certain cases be easier to establish responsibility for the waging of an aggressive war which is so clearly a gross violation of the United Nations Charter.”

Dating back 75 years, prosecuting leaders for formulating and executing state policies has been the core idea that undergirds criminalization of aggression. Ever since the first trials in the post-World War II era, it was clear that anyone below the policy level is beyond the scope of criminal liability for aggression. According to the leadership standard at the time, only a person in a position “to shape or influence the policy that brings about” the initiation of the war of aggression may be criminally responsible for such an outcome (High Command, p. 487). During the drafting process for the ICC prior to the Kampala Review Conference of 2010, the new “control or direct” leadership clause replaced Nuremberg’s “shape or influence.” In the Rome Statute, it is to be found in Articles 8bis (that defines the crime of aggression) and 25(3bis). Article 25 (“Individual criminal liability”) sets out modes of criminal lability in paragraph 3. The newly adopted paragraph 3bis states that “in respect of the crime of aggression, the provisions of this article shall apply only to persons in a position effectively to exercise control over or to direct the political or military action of a State.” Consequently, in order to prosecute perpetrators and accessories for the crime of aggression, the court first must ensure that as a prerequisite for criminal liability the defendants satisfied the leadership requirement of “control or direct.”

But what exactly is the meaning of “leadership” in this context?

Both “leaders” and “followers” are abstract concepts that do not give much guidance to criminal law theory. During the Nuremberg trials, a line separating “the guilty from the innocent…was set below the planners and leaders, such as Goering, Hess, von Ribbentrop, Rosenberg, Keitel, Frick, Funk, Doenitz, Raeder, Jodl, Seyss-Inquart, and von Neurath, who were found guilty of waging aggressive war, and above those whose participation was less and whose activity took the form of neither planning nor guiding the nation in its aggressive ambitions” (IG Farben, p. 1126). The responsibility of private individuals outside of formal state structures (such as industrialist) was explicitly recognized: “We do not hold that industrialists as such, could not under any circumstances be found guilty upon such charges” (see here).

The first time the leadership requirement was explicitly mentioned in an international document was in the International Law Commission’s (ILC) Draft Code of Crimes against the Peace and Security of Mankind in 1996 (Article 16). Calling on the Nuremberg precedent, the ILC reaffirmed that both the governmental and private sector leaders may be responsible for aggression as long as they played a decisive role in committing aggression (p. 43):

The perpetrators of an act of aggression are to be found only in the categories of individuals who have the necessary authority or power to be in a position potentially to play a decisive role in committing aggression. These are the individuals whom article 16 designates as “leaders” or “organizers”, an expression that was taken from the Charter of the Nuremberg Tribunal. These terms must be understood in the broad sense, that is to say, as referring, in addition to the members of a Government, to persons occupying high-level posts in the military, the diplomatic corps, political parties and industry, as recognized by the Nuremberg Tribunal, which stated that: “Hitler could not make aggressive war by himself. He had to have the cooperation of statesmen, military leaders, diplomats and businessmen.”

The following year, during the negotiations preceding the adoption of the Rome Statute, the new leadership clause “control or direct” was introduced (see February 1997 proposal of the German delegation, reprinted here). However, the precise normative content was never established. Crucially, the drafters clearly understood that the language of “control or direct” is sufficiently broad to include persons outside the state’s formal leadership. In 2009, the Special Working Group on the Crime of Aggression of the Assembly of States Parties report stated:

[T]here was general agreement on the inclusion of draft article 25, paragraph 3 bis, which would ensure that the leadership requirement would not only apply to the principal perpetrator, but to all forms of participation. It was noted that this provision was crucial to the structure of the definition of aggression in its current form. The view was also expressed that the language of this provision was sufficiently broad to include persons with effective control over the political or military action of a State but who are not formally part of the relevant government, such as industrialists. (p. 655-56 emphasis added).

Directing someone or something denotes ordering or commanding that person or thing with a very high degree of control over the conduct. Therefore, the term “direct” implies control that is close to absolute domination and requires in addition active participation toward executing state policy. “Control,” on the other hand, is a rather loose notion. The ILC held that in the context of the commission of wrongful conduct in international law, “control” denotes “domination over the commission…and not simply the exercise of oversight, still less mere influence or concern” (p.69). This is precisely how it should be understood in the definition of the crime of aggression: more than mere influence, less than absolute domination (the latter is more akin to the concept of “direct”).

In his concurring opinion in IG Farben, Judge Herbert held that the defendants (economic actors) “carried out activities indispensable to creating and equipping the Nazi war machine” (p. 1297). This is the line that draws the outer limits of criminal responsibility for aggression which separates “the guilty from the innocent”: an indispensable, “but for” contribution toward the formulation or execution of the state policy to use armed force, but not the absolute domination over the state conduct which is assumed only by the highest echelon of state leadership. McDougall is right to say that the leadership means “decisive say over… the political or military establishments of a State” (p.203). This authority, however, is not confined to the apex of the formal state military or political structure, but to anyone who played a decisive role in committing aggression, i.e., whose contribution was indispensable for the formulation of aggressive state policies.

Aiding and abetting

Complicity is a normative claim that someone contributed to the crime in a criminally relevant way. There are essentially two manifestations of complicity: influencing the perpetrator to commit the crime and assisting the perpetrator commit the crime (p. 342). The latter, sometimes termed as “aiding and abetting,” is usually what private actors are accused of when their criminal responsibility for aggression is called upon. Thus, Judge Herbert explained how the business executives of IG Farben assisted the aggressive war (p. 1297):

Farben and these defendants (members of the Vorstand), acting through the corporate instrumentality, furnished Hitler with substantial financial support which aided him in seizing power and contributed to keeping him in power; that they worked in close cooperation with the Wehrmacht in organizing and preparing mobilization plans for the eventuality of war; that they participated in the economic mobilization of Germany for war including the performance of a major role in the Four Year Plan; that they carried out activities indispensable to creating and equipping the Nazi war machine; that they participated in the stockpiling of critical war materials; that they engaged in vital propaganda, intelligence and espionage activities; that they used their business connections and cartels to strengthen Germany and to weaken the war potential of other countries; that they camouflaged and utilized assets abroad for war purposes; that they planned to take over the chemical industry of Europe and participated in plunder and spoliation of occupied countries ; and, that they participated in the utilization of slave labor on a vast scale to strengthen the German war machine.

Both McDougall and Heller believe that the new clause “control or direct” is a more stringent requirement than Nuremberg’s “shape or influence” and that effectively excludes private individuals from criminal liability. According to McDougall, the drafters of the Rome Statute consciously chose to restrict individual responsibility for aggression to those at the top of political or military leadership (p. 257). In his reading of IG Farben, Heller contends that the Farben defendants’ contribution was “but for,” i.e., indispensable to the realization of aggressive policies (p. 491). However, since the normative appreciation of the Farben defendants’ role was one of aiding, Heller argues that they could never satisfy the “control or direct” criterion since, as he says, the criterion of “indispensability” is the language of “shape or influence.” This seems to be a dominant position in the scholarship. In a recent post, Linde Bryk and Göran Sluiter lightly dismissed the possibility of prosecuting aiding and abetting for aggression due to the “control or direct” constraints.

That proposition cannot be asserted based on the plain reading of Article 25 of the Rome Statute (see para. 3bis). What’s needed is to understand properly the negotiating history. In that regard, the Special Working Group on the Crime of Aggression made it clear during the negotiations that there are two types of leaders that may satisfy “control or direct”: the principal perpetrator who commits the crime (“the leader type principal perpetrator” ), and the accessory who participates in the crime in a criminally relevant way.

Scholars suggesting different interpretations seem to find “control” (as a lower threshold in the leadership clause) irreconcilable with the normative scope of aiding and abetting. Indeed, according to the ICC’s “control over the crime” theory, only the perpetrator has control over the commission of the crime because “they decide whether and how the offence will be committed” (Lubanga, para. 330). An accessory who lends the gun does not control the shooting. The crucial difference between the ICC’s theory and “control” in the definition of the crime of aggression is that the latter refers to the state policy to commit an act of aggression, not to the actual act of commission (after all, it is a state-policy crime). Thus, a leader need not control the actual act of applying armed force; rather, as explained above, they play a decisive role in committing aggression by way of indispensable contribution toward the formulation and execution of aggressive state policies.

To illustrate this difference further, consider an example. When a state uses armed force, there are many individuals whose contributions are indispensable to that occurrence. For instance, a low-level subordinate who merely passes onto a fighter pilot the order to release bombs may be said to control the act of bombing. However, although he controls the act of commission in this case, his contribution is not indispensable toward the state’s policy to use armed force. Thus, but for his contribution the particular use of armed force would not have occurred. However, his non-performance would not decisively influence the state policy to use armed force, and the state would normally find another way to carry out an action to bring about effectively similar consequences. Accordingly, even though his contribution was essential for the realization of the particular act of the use of armed force, his role was not decisive toward the formulation nor execution of the state policy to commit aggression.

To sum up, if we accept that the notion of leadership in the crime of aggression lends itself to a normative determination that the individual played a decisive role in committing aggression, there are no conceptual constraints to prosecute private individuals for complicity in aggression.


Aggression is the product of a joint endeavor of different national and transnational structures of power. Prior to inter-state violence, plans are made, public debates are shaped, and advice is given by governmental and non-governmental experts. Media agencies conduct propaganda, business enterprises look for profit, and the parliament may take a vote, and, eventually, the high-state military and political leadership gives the final command. In such a constellation, many individuals contribute to the creation of the overall act that makes up the crime of aggression. This article demonstrates that private individuals may meet the “control or direct” leadership requirement and consequently be criminally liable for aiding and abetting aggression if their contribution toward the formulation of aggressive state policies was truly indispensable. It bears stressing that indispensable contribution does not automatically entail criminal responsibility. The prosecution would also need to prove the necessary actus reus and mens rea, which will dramatically reduce the scope of criminal responsibility to only a few most responsible individuals for aggressive war. In this vein, the Nuremberg legacy will be well preserved, and the sharp focus of international criminal law pointed toward the most culpable.


Photo credit: Russian businessman Yevgeny Prigozhin, who has been linked to the Wagner Group and Internet Research Agency, attends meeting with investors at the 2nd Eastern Economic Forum on September, 2, 2016 in Vladivostok, Russia (Mikhail Svetlov/Getty Images)